CD200Fc reduces LPS-induced IL-1β activation in human cervical cancer cells by modulating TLR4-NF-κB and NLRP3 inflammasome pathway

Abstract

Chronic inflammation plays an important role in tumorigenesis of cervical cancer. CD200Fc, a CD200R1 agonist, has been found to have anti-inflammatory effects in autoimmune diseases and neuro-degeneration. However, the anti-inflammatory effect of CD200Fc on cervical cancer has not yet to be completely understood. This study investigated the anti-inflammatory effects and mechanisms of CD200Fc in LPS-induced human SiHa cells and Caski cells. SiHa cells and Caski cells were stimulated with 40 μg/ml LPS under different concentrations of CD200Fc for 90 min or 12 hours. The mRNA and protein levels of pro-IL-1β, cleaved-IL-1β and NLRP3, as well as the protein level of cleaved caspase-1, were significantly increased in LPS-induced SiHa cells and Caski cells. LPS stimulation did not change ASC and pro-caspase-1 expression. CD200Fc down-regulated protein expression of cleaved caspase-1 and mRNA and protein expression of pro-IL-1β, cleaved-IL-1β and NLRP3. In addition, the protein levels of TLR4, p-P65 and p-IκB, as well as the translocation of P65 to nucleus, were significantly increased in LPS-induced SiHa cells and Caski cells. LPS stimulation did not change t-P65 and t-IκB on protein levels, which were components of TLR-NF-κB pathway. CD200Fc down-regulated protein expression of TLR4, p-P65 and p-IκB and inhibited the translocation of P65 to nucleus in LPS-induced SiHa cells and Caski cells. These results indicated that CD200Fc appeared to suppress the inflammatory activity of TLR4-NF-κB and NLRP3 inflammasome pathway in LPS-induced SiHa cells and Caski cells. It provided novel mechanistic insights into the potential therapeutic uses of CD200Fc for cervical cancer.